feat: enable difffold to gin-diff

Author: lambdalisue

denops/gin/command/diff/edit.ts

@@ -15,6 +15,7 @@ import {
 import * as buffer from "jsr:@denops/std@^7.0.0/buffer";
 import { exec as execBuffer } from "../../command/buffer/edit.ts";
 import { init as initDiffJump } from "../../feat/diffjump/jump.ts";
+import { init as initDiffFold } from "../../feat/difffold/fold.ts";
 
 export async function edit(
   denops: Denops,
@@ -90,4 +91,7 @@ export async function exec(
 
   // Initialize diff jump functionality
   await initDiffJump(denops, bufnr, "diff");
+
+  // Initialize diff fold functionality
+  await initDiffFold(denops, bufnr);
 }

ftplugin/gin-diff.vim

@@ -3,6 +3,8 @@ if exists('b:did_ftplugin')
 endif
 runtime ftplugin/diff.vim
 
+setlocal foldlevel=1
+
 if !get(g:, 'gin_diff_disable_default_mappings')
   nmap <buffer> <CR> <Plug>(gin-diffjump-smart)zv
   nmap <buffer> g<CR> <Plug>(gin-diffjump-old)zv